1. Field of the Invention
The present invention relates to a coin discrimination apparatus used in a vending machine or a coin exchange machine.
2. Prior Art
In a coin discrimination apparatus, a discriminating mechanism such as an electronic discrimination unit or cradle is provided in a coin path formed between two plates, and a coin path selector is provided to discriminate and store coins.
A conventional coin discrimination apparatus discriminates the authenticity/counterfeitness of coins and their denominations in accordance with their diameters, thickness, weights or the like. For this reason, the discrimination precision must be high so that erroneous discrimination can be prevented.
In a conventional coin discrimination apparatus having an electronic discrimination unit, solenoids for the respective denominations are actuated in response to discrimination signals from an electronic discrimination unit so as to discriminate coins in units of their denominations. The coins of each denomination are guided to the corresponding coin path. For this reason, a plurality of solenoids must be provided in accordance with the number of denominations of coins which are inserted in the coin discrimination apparatus. Therefore, the coin discrimination apparatus has higher cost than that having a single discrimination member.
Furthermore, in the conventional coin discrimination apparatus, a discrimination member such as a cradle is mounted at the side of one plate, and a solenoid for driving a selector member is mounted at the side of the other plate. Particularly, in a conventional coin discrimination apparatus having as a return path a space (at the side of one plate) other than the space defined between these two plates, for example, when a coin is guided into a space other than that between the two plates, a solenoid is disposed on the other plate which does not define the return path. A selection member is actuated by the solenoid to cross the coin into the return path. In this manner, the coin return path can be assured without being interfered by the solenoid and the like.
On the other hand, a circuit board having an electronic circuit for controlling the coin discrimination apparatus is mounted on one plate. As described above, the discrimination member, the selection member and the solenoid are arranged at two sides of the coin path, so that the circuit board must have a specific shape so as not to interfere with the solenoid mounted on the plate. The circuit board is divided into pieces which are then mounted on the plate, thus resulting in a time-consuming and cumbersome operation. In addition to this disadvantage, extra repair is required in addition to replacement of the circuit board at the time of repair and maintenance. In addition, the plates for forming the coin path are easily contaminated by dust and oil attached to the coins.
In addition, the two plates of the coin discrimination apparatus are also contaminated by dust or powders with steam in accordance with the type of item sold by a vending machine. Dust laden stream or the like cause rusting of component parts of the coin discrimination apparatus, and coins may not then be properly guided or discriminated. In this case, dust or the like must be removed from the surfaces of the plates and the components on the plates. For this purpose, a coin discrimination apparatus with a detachably mounted device plate as one plate serving as a coin discrimination member is proposed in Japanese Utility Model Publication No. 55-37986. According to this conventional coin discrimination apparatus, one side of the device plate having the coin discriminating member is mounted on an upper portion of a main plate as the other plate to be freely opened through a shaft. At the same time, a spring is wound around the shaft to urge the device plate toward the main plate. The intermediate portion of the spring is bent and extends toward the inner surface of the device plate. An end portion of the spring is bent and engaged with an end of an engaging window formed in the main plate. In this manner, the device plate is mounted on the main plate.
However, according to the conventional coin discrimination apparatus described above, the construction becomes complicated, and assembly operation becomes time-consuming. In addition to these disadvantages, it is cumbersome to attach the device plate or detach it from the main plate. The device plate is urged against the main plate by only the spring, so that the biasing force of the spring must be large. As a result, a strong force by the spring acts on the shaft, so that a very rigid material must be used for the shaft, resulting in a higher cost.